Leather Water Stain Removal
 

I have & had stains on my dash board from a leaky windshield. Through searching the internet, found a discussion on Platz Mall, as follows:
you should be able to remove water stains as follows:
mix a dilute solution of dish washing liquid.
using a sponge, dip into solution & squeeze to form foam.
dab the foamy sponge onto the affected area, Note: don't rub.
dab dry with a soft absorbent cloth.
you may need to repeat this procedure several times until the stain fades out.
be certain to apply a leather conditioning cream after all the stain is removed.
Good Luck!